package com.yb.custom.annotation.log.util;

import lombok.extern.slf4j.Slf4j;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * @author yangbiao
 * @date 2022/3/8
 */
@Slf4j
public class IpUtils {

    /**
     * 根据请求获取真实IP地址
     *
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request) {
        String unknown = "unknown";
        String ipAddress = request.getHeader("x-forwarded-for");
        if (ipAddress == null || ipAddress.length() == 0 || unknown.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || unknown.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || unknown.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getRemoteAddr();
            String localIp = "127.0.0.1";
            String localIpv6 = "0:0:0:0:0:0:0:1";
            if (ipAddress.equals(localIp) || ipAddress.equals(localIpv6)) {
                // 根据网卡取本机配置的IP
                InetAddress inet;
                try {
                    inet = InetAddress.getLocalHost();
                    ipAddress = inet.getHostAddress();
                } catch (UnknownHostException e) {
                    log.error("未知的IP信息:{}", e.getMessage(), e);
                }
            }
        }
        //对于通过多个代理的情况,第一个IP为客户端真实IP,多个IP按照','分割
        String ipSeparate = ",";
        int ipLength = 15;
        if (ipAddress != null && ipAddress.length() > ipLength) {
            if (ipAddress.indexOf(ipSeparate) > 0) {
                ipAddress = ipAddress.substring(0, ipAddress.indexOf(ipSeparate));
            }
        }
        return ipAddress;
    }

}
